Yes i have a new asrock h110 btc + running with 8 nvidia cards and wanted to add some AMD's but wanted to see the miner's limitation...i really dont want to open another instance
With Claymore you will have difficulties running Nvidia plus AMD cards together on a single miner, however you can download 2 versions of Claymore, the CUDA version for Nvidia (which I believe you already have) and then download the Open CL AMD version when you add the AMD cards. Run the versions separately and things should be fine.
If you can't then download Nicehash, with it it is very easy to run a single instance with all kind of cards you may have. As you can see in the picture below.